Manufacture of coloring matters



Patented Oct. 8, 1940 PATENT OFFICE MANUFACTURE OF COLORING MATTERS 'Max Wyler, Blackley, Manchester, England, as-

signor to Imperial Chemical Industries Limited, a corporation of Great Britain No Drawing. Application November 4, 1938, Serial No. 238,809

6 Claims.

\ This application is a continuation-in-part of my copending application Serial No. 82,147, filed May 2'7, 1936.

This invention relates to the manufacture of 5 coloring matters of the phthalocyanine series. More particularly this invention deals with the manufacture of magnetic metal-phthalocyanines, namely those of iron, nickel, and cobalt.

It is an object of this invention to provide an eillclent and economical process for producing these metal-phthalocyanines. Other and further objects of this invention will appear as the description proceeds.

In British Patents Nos. 322,169, 389,842 and 410,814, there are described a series of coloring matters obtainable for instance by reacting phthalonitrile and copper or copper compounds; ortho-cyano-benzamide with iron, nickel, chromium, lead or manganese in the form of free 80 metal or in the form of oxides, sulfides or carbonates; or by passing ammonia into a melt of phthalic anhydride, phthalamide or phthalimide in the presence of a metal or metal oxide or sulfide. 2b The coloring matters so obtained have been named generically metal-phthalocyanines, and

individually copper-phthalocyanine, iron-phthalocyanine, etc.,.according to the metal which they contain. A more detailed discussion of their 30 structure is contained in a series of articles by Linstead et al., in the Journal of the Chemical Society for 1934, pages 1016 to 1039.

The processes of the two earlier British patents above mentioned have the advantage of starting 86 with relatively inexpensive initial material. The

organic initial material mentioned in these patents is phthalic anhydride, phthalmide, phthalic acid diamide and ortho-cyano-benzamide, the

corresponding derivatives of naphthalene and 40 anthracene, or nuclear substitution derivatives of these compounds. These processes, however, do not give such good yields and such high quality products as that of the subsequent process of Br. Patent No. 410,814, wherein an orthoarylene-di- 45 cyanide is employed. The latter, however, has

the disadvantage that the initial material is relatively more expensive, and has to be specially synthesized from the initial material first mentioned.

The present invention relates to a process for 50 the manufacture of the iron, nickel and cobalt phthalocyanines in good yield from starting materials difierent from those hitherto used and easily accessible, or in improved yield when known ate is heated with substancesyielding cobalt, nickel or iron (1. e. the metals themselves or salts,

e. g., halides or acetates) and with an aminosulphonic acid or a salt thereof, then cobalt, iron or nickel phthalocyanines (as the case may be) 5 are formed.

Usually the metals are added to the reaction mixture in the form of salts, and the reaction then proceeds smoothly at 220 C. to 260 C. conveniently at 240 C. to 250 0.; when free metals 10 are used, they are to be in a state of fine division and a somewhat higher temperature is needed.

The process appears to involve a dehydration, and agreeably to this interpretation there may be used instead of an ammonium phthaiate anll other derivative of the corresponding phthalic acid. Thus the phthalic diamides, or the salts of the phthalamic acids or the o-cyanobenzoic acids, or the o-cyanobenzamides may be used. Also, as the ammonium phthalates may be formed in situ, it is possible to use a phthalimide or a phthalic anhydride or a free phthalic acid, sufficient ammonia being of course provided, as by use of another ammonium salt. In this respect the invention may be regarded as an improvement on that described in British specification No. 322,- 169, the improvement being that the process is technically more feasible and in particular that higher yields are obtained. The same may be said when cyanobenzamides are used (compare British specification No. 389,842).

The term an aminosulphonic acid or a salt thereof is intended to include aminosulphonic acid (sulphaminic' acid) and iminodisulphonic acid and their saltsand the nitrilo-sulphonates (see Inorganic Chemistry, Ephraim, trans. Thorne, London and Edinburgh, 1926, page 540).

More particularly, I select as initial material phthalic acid or a salt thereof, for instance ammonium phthalate or one of the compounds ob- 40 tainable, at least theoretically, in the successive dehydration and deamidation of ammonium phthalate, for instance phthalamic acid, ammonium phthalamate, phthalic anhydride, phthalic acid diamide (phthalamide), phthalimide, or ortho-cyano-benzamide. In lieu of the above particular compounds, their nuclear substitution derivatives may be employed, for instance monoor di-halogen, monoor di-nitro compounds, sulfonic acid derivatives and others. ,Also, in lieuof the mentioned compounds of the phthalic acid family, the corresponding derivatives from naphthaleneor anthracene-orthodicarboxylic' acids may be employed. More specifically, 4-chlorophthalic anhydride, and 3- and 4-nitrophthalic anhydrides or other corresponding derivatives of the respective acids may be mentioned. The sulphophthalic acids are likewise adapted to serve as starting materials, and give characteristic products, soluble in. water.

The said initial material is mixed with a salt of one of the metals above mentioned, for instance ferrous or ferric chloride, nickel chloride, ferrous or ferric acetate or the corresponding amino-sulfonates.

To these is added an amino-sulfonic acid or a alt thereof, for instance amino-sulfonic acid, im' \odisulfonic acid, salts thereof or salts or nitrilo-trisulfonic acid (N (SOaH)3). Since the presence of ammonium compounds is favorable to the reaction, it is preferable to select as salts of the said amino-sulfonic acids their corresponding ammonium compounds. Alternatively, one may select the amino-sulfonates in the form of an alkali-metal salt or in the form of a salt of that metal whose phthalocyanine it is desired to prepare, for instance nickel-amino-sulfonate, etc.

Without limiting my invention to any particular procedure, the following examples are given to illustrate my preferred mode of operation. Parts mentioned are by weight.

mp e 1.'7 parts of ammonium phthalate, CsH4(COONH4) 2, '7 parts of ammonium aminosulfonate and 2 parts of nickel chloride are well mixed and heated. The mixture becomes partly fluid at about 220 C. and blue at about 240 C. It is kept at 240 to 250 C. until formation of coloring matter is complete. The mixture is cooled, ground, boiled with water and filtered. The solid matter is dried, dissolved in 10 parts of 94% sulfuric acid, poured into 100 parts of water, filtered, washed free of acid and dried. Nickel phthalocyanine is thus obtained in good yield and constitutes a green pigment.

Example 2.--7 parts of phthalamide (phthalic acid diamide), 5 parts of ammonium sulfamate and 2 parts of nickel chloride are well mixed and heated at 220 to 240 C. until no more coloring matter is formed. It is isolated as in Example 1 and appears to be the same compound.

Example 3.-The procedure is the same as in Example 2, except that 2 parts of ferric chloride are employed in lieu of nickel chloride. The product, iron phthalocyanine, is a dull green pigment.

Example 4.-66 parts of phthalimide, 90 parts of ammonium aminosulionate and 16 parts of anhydrous nickel chloride are mixed and heated for 2 hours at 220 C. The product is isolated as in Example 1. It is a green coloring matter.

In a similar manner, by using cobaltous chloride, the corresponding cobalt phthalocyanine may be prepared. It is a blue pigment.

Other amino-sulf0nic compounds which come into consideration for the purpose of this inven-- tion are amino-sulfonic acid itself, trisodiumnitrilo-sulfonic acid and sodium-dipotassium nitrilo-sulfonic acid. These may be used in lieu of ammonium sulfamate in those cases where the initial material selected has itself suflicient nitrogen to form the hypothetical, transient oarylene-dicyanide, as for instance in Examples 1, 2 and 3 above.

In all the examples above, solvents or suspension media may be employed to assist in the manipulation. Suitable media for this purpose are indifferent organic liquids of conveniently high boiling point, for instance naphthalene,

beta-methyl-naphthalene or crude chloro-naphthalene.

The magnetic-metal-phthalocyanines are usefulpigments, the iron and nickel compounds being greenish blue in shade. For technical purposes pigments must satisfy various demands in which particular physical properties (fineness of division, non-crystalline form, freedom from impurities) are of great importance. The products of the present invention in its preferred embodiments are obtained in such a form that they are excellently suited for use as pigments; the process being such that any excess of reagent is readily removed, and the shades of the pigments being very bright.

Ammonia may be passed through the reaction mass if desired.

Other variations and modifications may be made, within the scope of the prior British patents above mentioned, as will be readily apparent to those skilled in the art.

It will be clear from the above discussion and examples that my invention is applicable to the manufacture of metal-phthalocyanines by starting out with the respective metalliferous reagent, that is the respective free metal or a salt thereof, and using any of the following organic or mixed initial materials:

Ammonium phthalate C|3H4(C00NH4)2 Phthalic acid ammonia e 4(C00H) 2NH Phtlialic anhydride ammonia CoH gCO)2O 2NH Phthalic acid dlamide (36H; CONHz 2 Phthallmide ammonia CH4(CO) NH NH also, nuclear substitution derivatives of the above compounds, as well as the corresponding derivatives of the naphthalene or anthracene series.

The organic compounds of this series may all be considered as derived, at least in theory, from the corresponding diammonium-ortho-arylenedicarboxylate by dehydration and deammoniation; that is, elimination of H20 units and of NH3 units. Furthermore, when the typical formula of a phthalocyanine is considered, that is [CcH4(CN) 2]4.M wherein M is a bivalent metal, it appears that the initial material jointly with the ammonia contained in itself or furnished by the reaction mass, probably forms an orthoarylene-dicyanide in transient state during the course of the reaction. These two factors tie the above diversified group of materials into a single family with readily determinable common characteristics.

I claim:

1. The process of producing a magnetic metal phthalocyanine which comprises heating initial material adapted to form an ortho-arylene-dicyanide by dehydration, with a reagent adapted to furnish a magnetic metal, in the presence of ammonium sulfamate.

2. The process of producing iron phthalocyanine which comprises fusing together ammonium sulfamate, a halide of iron and initial material selected from the group consisting of ammonium phthalate, phthalic acid and ammonia, phthalic anhydride and ammonia, phthalic acid diamide, phthalamide and ammonia, o-cyano-benzamide, phthalamic acid and ammonia, ammonium phthalamate and the ammonium salt of o-cyanobenzoic acid.

3. The process of producing nickel phthalophthalimide, a halide of a magnetic metal, and ammonium sulfamate.

5. The process of producing nickel phthalocyanine which comprises heating together at a temperature between 220 and 250 C., phthalimide, ammonium sulfamate and nickel chloride.

6. The process of producing nickel phthalocyanine which comprises heating together at a temperature between 220 and 250 0., ammonium phthalate, ammonium sulfamate and nickel 10 chloride.

MAX WYLER. 

